1. Field of the Invention
The present invention relates to a communication system comprising a network and an information multiplexing device which device transmits information cells from one of its accesses to another access and comprises:
a plurality of access terminals for users who have information to be transmitted to a certain destination at a certain rate, PA1 a plurality of connecting terminals for a plurality of accesses of said network, PA1 a plurality of service circuits which include queue elements for storing user data and for producing on the data outputs the cells to be transmitted, PA1 a common data line interconnecting the data outputs of said service circuits, PA1 a plurality of network circuits comprising output circuits whose inputs are connected to said data line and whose outputs are connected to said connecting terminals. PA1 an assigning element for assigning periods of time in which cells can be taken from said data line to each one of the output circuits as a function of the flow rate of said output circuits.
ATM networks are increasingly widespread and to utilize them to the maximum of the possibilities they present, it is suitable to multiplex the data the user wishes to transmit.
2. Description of the Related Art
A communication system of this type comprising a device that is capable of performing the multiplexing operation is known from French Patent Application No. 2 670 972.
This known device is formed by input nodes whose functions can be compared with said service circuits, and output nodes that can be compared with the network circuits.
All the nodes, both output and input nodes, are to have identical characteristic features because mixing operations are to be carded out for which any cell at the input of whatever input node can go to the output of whatever output node. However, with respect to multiplexing operations, when users are to be connected to an ATM network, they can use links which ensure different rates: fiber optics, telephone lines . . . The known device does not provide any special measure to adapt the output nodes to the rate offered by the link to which they are connected. As a result, queues occur at the output nodes in order to partly absorb these rate discrepancies.